Method of making an oscillating set for clock work-movement



H. HAUSHEER Nov. 29, 1966 METHOD OF MAKING AN OSCILLATING SET FOR CLOCK WORK-MOVEMENT Filed Dec. 16, 1964 2 Sheets$heet 1 Nov. 29, 1966 H. HAUSHEER 3,287,799

METHOD OF MAKING AN OSCILLATING SET FOR CLOCK WORK-MOVEMENT I Filed Dec. 16, 1964 2 Sheets-5heet E;

United States Patent M 3,287,799 METHOD OF MAKING AN OSCILLATING SET FOR CLOCK W0RK MOVEMENT Hermann Hausheer, Nenchatel, Switzerland, assignor to Axhor Socit Gnrale de llndustrie des Pieces Pivotes, Neuchatel, Switzerland, 21 firm Filed Dec. 16, 1964, Ser. No. 418,668 Claims priority, application Switzerland, Dec. 18, 1963, 15,632/63; Nov. 24, 1964, 15,122/64 1 Claim. (Cl. 29178) The present invention relates to a method of making an oscillating set for clock work-movement,

The oscillating 'set of watches comprises a staff on the shoulders of which are fitted the balance, the escapement roller, and the collet adapted to render the inner extremity of the balance-spring integral with the set. The staff is provided with pivots, by means of which it can oscillate in bearings of the watch-frame.

Such an arrangement has the drawback that it cannot ensure the perfect concentricity of the balance, of the roller, and of the collet with respect to the pivots.

Moreover, the fixation, by riveting or driving on the balance staff of the roller and of the balance, give rise to tensions resulting in a distortion of the assembled parts, thus increasing the lack of concentricity.

It has been endeavoured to meet these drawbacks by fitting the balance and the collet on extensions of the. roller, and thereupon fixing the whole assembly on a cylindrical balance staff. However, the riveting of the balance on that roller collapses the roller, which leads to unwanted distortion.

Finally, it has been endeavoured to fit the roller, the balance and the collet on a cylindrical staif. While in such a form of embodiment, the problem of concentricity is solved, however, other drawbacks arise, due to the absence of axial stops between the constituent parts.

The object of the present invention is precisely to provide a method of making an oscillating set, in which the centering and alignment achieved are better than what has been obtained to this day. l

The oscillating set for clock work-movement according to the invention, comprises a cylindrical staff, provided with pivots, a collet for fixing the balance-spring, a bushing provided with two protrusions forming the smaller and the main escapement rollers, and with a collar which is adapted to receive the balance. Said oscillating set is characterized in that the bore of said bushing is of reduced cross-section in front of the collar, in order that, when the cylindrical staff is force-fitted into the bore of the bushing, the diameter of the collar is caused to increase, whereby the balance is made integral with said bushing,.

The invention will now be described with reference to the accompanying drawing, wherein:

FIGURES 1 and 2 are a general view and a detail view respectively in cross-section, of a first form of embodi-. ment, and

FIGURES is a vertical section of a second form of embodiment.

The oscillating set according to FIG. 1 comprises, on the one hand, a cylindrical staff 1 provided with pivots 2, and on the other hand, a bushing 3 forming the escapement roller and provided with two protrusions 3a and 3b acting as the smaller and the main rollers respectively, a collar 3c on which is placed the balance 4, and the collet 5 adapted to retain the extremity of the balancespring (not shown).

3,287,799 Patented Nov. 29, 1966 The impulse pin 6 is fitted in an opening to the protrusion 312, whereas the protrusion 3a has a notch 7,. necessary for actuating the lever escapement.

Bushing 3 (FIG. 2) has a bore 8, the cross-section of which is reduced at 8a, in front of the collar 30. Said collar has a diameter slightly smaller than that of the hole made in the balance-arm, so that it can easily pene-, trate into said hole. An appropriate choice of the diameters permits slight blocking of the cylindrical staff 1 with respect to bore 8.

The mounting of the constituent parts of that oscillating set is achieved as follows:

The balance for 4 is first placed on the collar 3c, then the staff 1 is driven into bore 8 in the direction of arrow 9.. Whenever that staff penetrates into portion 8a of smaller cross-section, it will distort that portion, thereby increasing the diameter of collar 30 which is then squeezed in the balance bore. The collet provided with the balancespring is then driven on staff 1. Said collet will rest, by its lower face 511, on the upper face 3c of the bushing.

In View of the increase of the collar diameter, the balance is tightly fixed to the bushing, without it being necessary to proceed with a riveting, as is usually the case.

The set, once its elements are mounted, keeps a perfect concentricity since none of these elements has undergone stresses likely to cause a collapse or a distortion.

it is possible to rectify the diameter of staff 1 with respect to its pivots.

The assembly thus achieved has, as regards the centering and the alignment of its elements, a precision never achieved with the methods or devices known to this day.

The oscillating set shown in FIGv 3 comprises, on the one hand, a pivoting cylindrical staff 1, and, on the other hand, a bushing forming the escapement rollers and having two protrusions acting as the smaller and the main rollers respectively, a collar on which is placed the balance 4, and a collet 5 adapted to retain the extremity of the balance-spring (not shown).

The impulse pin 6 of the main roller is fitted in an opening of the protrusion 3b, whereas protrusion 3a is, provided with a notch 7, necessary for operating the lever escapement Prior to the mounting, the staff is of a diameter slightly greater than the bore of the bushing, and the lower diameter of the hole made in the balance-arm is slightly smaller than the diameter of the collar.

The mounting is achieved by forcing the balance on the collar, then by driving the staff in the bushing. The collet bearing the balance-spring is then drive in the staff, on which it is retained by the collar. The bushing is thus submitted to opposed internal and external pressures which hold it tightly.

The method of the invention is rapid and can easily be effected by automatic means.

What I claim is:

Method for making an oscillating set for a clock workmovement comprising the steps of providing a bushing having at one end thereof a collar and an axial bore the diameter of which is reduced in front of said collar near,

More; over, and still in order to suppress the lack of centering,

3 4 of said collar so as to distort the same in its section of 1,784,755 12/1930 Rosenberg. reduced diameter thereby increasing the diameter of said, 2,125,866 8/1938 Bell 29-178 collar and squeezing the same into said hole of said bal-. 2,263,484 11/ 1941 Brendler 58140 ance to make said balance and staff rigid, and then. FOREIGN PATENTS driving a collet provided With a balance spring on said. 5

staff until said collet rests against said upper face of 1,216,100 11/1959 Franceaid bushing, 1,301,939 7/1962 France.

546,908 3/1932 Germany. References Cited by the Examiner UNITED STATES PATENTS 217,291 7/1879 Lambert 58-140 744,719 11/1903 Church 58-140 JOHN F. CAMPBELL, Primary Examiner.

GERALD F. BAKER, THOMAS H. EAGER, Examiners. 

